SQL> execute dbms_mview.refresh ('TX_FAIL_LOG_DAY_MV', 'f');
BEGIN DBMS_MVIEW.REFRESH ('TX_FAIL_LOG_DAY_MV', 'f'); END;
*
ERROR at line 1:
ORA-12052: cannot fast refresh materialized view BIDATA.TX_FAIL_LOG_DAY_MV
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2563
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2776
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2745
ORA-06512: at line 1
Solution:
The Oracle provided DBMS_MVIEW.explain_mview procedure was used to analyze each of the existing materialized views FAST REFRESH capabilities and write the results to the MV_CAPABILITIES_TABLE. Now using DBMS_MVIEW.explain_mview procedure I will analysis the possible reason why the materialized view cannot fast refresh.
SQL> EXEC dbms_mview.explain_mview('TX_FAIL_LOG_DAY_MV');
PL/SQL procedure successfully completed.
SQL> SELECT capability_name,
possible,
substr(msgtxt,1,60) AS msgtxt
FROM mv_capabilities_table
WHERE capability_name like '%FAST%';
| CAPABILITY_NAME |
POSSIBLE |
MSGTXT |
| REFRESH_FAST |
Y |
|
| REFRESH_FAST_AFTER_INSERT |
N |
mv log does not have all necessary columns |
| REFRESH_FAST_AFTER_ONETAB_DML |
N |
see the reason why REFRESH_FAST_AFTER_INSERT is disabled |
| REFRESH_FAST_AFTER_ANY_DML |
N |
mv log does not have sequence # |
| REFRESH_FAST_AFTER_ANY_DML |
N |
see the reason why REFRESH_FAST_AFTER_ONETAB_DML is disabled |
| REFRESH_FAST_PCT |
Y |
So you can see from the analysis that the log table does not have all the necessary columns. I have added the missing column.
SQL> ALTER MATERIALIZED VIEW LOG ON BIDATA.TX_FAIL_LOG_HOUR_MV ADD(CONTENTPROVIDERSERVICEID);
SQL> execute dbms_mview.refresh ('TX_FAIL_LOG_DAY_MV', 'f');
BEGIN DBMS_MVIEW.REFRESH ('TX_FAIL_LOG_DAY_MV', 'f'); END;
*
ERROR at line 1:
ORA-12052: cannot fast refresh materialized view BIDATA.TX_FAIL_LOG_DAY_MV
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2563
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2776
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 2745
ORA-06512: at line 1
Still we are getting the error because first we require a complete refresh. After the complete refresh fast refresh will work.
SQL> execute dbms_mview.refresh ('TX_FAIL_LOG_DAY_MV', 'c');
PL/SQL procedure successfully completed.
Elapsed: 02:27:28.10
SQL> execute dbms_mview.refresh ('TX_FAIL_LOG_DAY_MV', 'f');
PL/SQL procedure successfully completed.
Elapsed: 00:01:38.61